DTV HD compression rate?
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It really depends on the channel, along with what satellite the channel is coming off of. They use both DVB-S2 on the newer satellites, H.264/mpeg-4 AVC for local channels & some of the other channels on the older birds that are still in use. It is a Variable bit rate, so it can vary at different rates, depending on what the channel is showing.
You are talking about Directv /D* here, right, not DTV (Digital TV) .
Just wanted to clarify.
When I first saw it, I thought DTV, not Directv, even though its in the D* section.
As broe67 says, there is no specific number anyway. Channels are allocated bandwidth using adaptive statistical multiplexing, based on the channels requirments - fast action sports gets more bandwidth. At one time there was a group monitoring bandwidth but I haven't seen any posts on this for a long time.
Here's some data though, which I think is still valid. An HD transponder has about 32 Mbps capacity (after you remove guard bands and such). DirecTv puts 5 HD channels per transponder, although this might be increasing with better encoding. I seem to remember at one time the DirecTV contract with HBO required DirecTv to give HBO's main channel 8Mbps although this was some time ago.
But my question is - why are you asking? You can't really compare bitrates between providers because they all use different encoders and some are more effective than others. (This is apart from the MPEG-2 vs MPEG-4 differences, MPEG-4 is much more efficient than MPEG-2 in delivering the same PQ)
Me, too. I was going to comment that it varies by the presence and quantity of subchannels. Then I saw Directv in the body of the post. Very confusing.
I would imagine that D* does put 6 channels on some transponers, more than likely they can do that alot with a group of channels that are mainly stationary, such as talking head shows, that type of thing.
I did say in my post that the number may be increasing above 5, with better encoders. As you say, if there's no fast action, 6 would almost certainly be OK. I have not looked for a few weeks, but I did see some TPs with 6 when I looked.
I'm trying to get my stuff set up so I can capture in HD from my DirecTV DVR to the computer. I just figured if the bitrate was always below 10 there wouldn't be much sense in setting the capture bitrate at 20....I understand the variablity of it all, I just hadn't read much on the bitrates that they use...
As for DTV/Digital TV/DirecTV/D* - sorry, I didn't even think of DTV being misread as Digital TV.
As for DTV/Digital TV/DirecTV/D* - sorry, I didn't even think of DTV being misread as Digital TV.
Locals on Spot beams, they will cram more on each Transponder. There are some dedicated Transponders, that have two to three channels only on them, per contract with that provider. They do that, so they can roll over channels from a bad transponder, to a good one if needed.
With the Olympics coming up, I am sure that they are going to request as much bandwidth as they can, to be able to give the best PQ, along with probably a 4k feed if we are lucky, since 3D is dying.
Yes, as always. Only thing is, everything major will be tape delayed this year again, just like Beijing & Australia.
and CBC as well.:
and I goofed. It starts February 6th
Really ?
It starts on a Thursday ?
I thought the opening ceremony was always on a Friday ...
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